第1个回答 推荐于2016-11-23
#include <iostream>
#include <fstream>
using namespace std;
int main()
{
ofstream oufile("file.txt",ios::binary);
char ab[1000];
cin.get(ab,1000,'#');//参数=>数组地址,地址长度,输入结束符号
for(int i=0;ab[i]!='\0';i++)//加密
{
if(ab[i]<='Z'&& ab[i]>='A')
ab[i]=(ab[i]-'A'+4)%('Z'-'A')+'A';
else if(ab[i]<='z' && ab[i]>='a')
ab[i]=(ab[i]-'a'+4)%('z'-'a')+'a';
}
oufile<<ab;
oufile.close();
ifstream xx("file.txt");
char ch;
while(xx>>noskipws>>ch)//解密
{
if(ch<='Z' && ch>='A')
ch=(ch+'Z'-'A'-4-'A')%('Z'-'A')+'A';
else if(ch<='z' && ch>='a')
ch=(ch+'z'-'a'-4-'a')%('z'-'a')+'a';
cout<<ch;
}
return 0;
}本回答被提问者采纳